I do multiple short etches (5 mins ish), scrubbed with a pan scourer and dish soap in between (like my american lingo ? ) When you can just about feel a bit of topography stop and clean it up. You can always etch more after if you dont like the effect.
Im not into this 'setting the oxides' thing, I like to know all scuz has gone from the blade as I mostly do chefs knives. I sand with 1000g wet and dry on a hard backing to hit the high spots, and thats what makes it pop. Also hit it with some flitz or metal polish, on a piece of leather glued to a hard backing.
One observation I have